[The effect of low frequency electrical stimulation on bone tissue regeneration].

The study was performed on 30 male rats of Wistar line (weight 330-360 g, age 3.5 months).In an experimental model of damage to the femur bone in the hip joint studied the effect of low frequency electrical stimulation of the damaged area on the rate of regeneration of bone.

[Heterogeneity and possible structure of mesenchymal stromal cell population].

Mesenchymal stromal cells (MSC) represent a heterogeneous population of cells that differ in morphology, phenotype, ability to grow and differentiate, and other properties. Differences between MSC are related in part to the influence of their microenvironment. However, the heterogeneity of these cells also is due to their parent-progeny relationship.

[Cellular composition and regulatory function of fetal liver stroma].

Hematopoietic differentiation and formation of hepatic tissue both take place in mammalian liver during its prenatal development. Hematopoietic and hepatic stem cells self-renew, proliferate and differentiate within specific microenvironment that is organized by stromal elements. Stroma of developing liver consists of different cell populations such as mesenchymal stromal cells, Ito cells, portal fibroblasts and myofibroblasts, vascular endothelial and smooth muscle cells, cells undergoing epithelial-to-mesenchymal transition.

[The sensitivity of mesenchymal stromal cell subpopulations with different times of adhesion property manifestation and derived from hemopoietic organs to growth factors EGF, bFGF, and PDGF].

The action of three growth factors (EGF, bFGF, and PDGF) on mesenchymal stromal cell (MSC) subpopulations from mature bone marrow (BM) and rat embryo liver (EL) was investigated. These cells are plastic-adhesive and have different rates of adhesion (AC1-AC4 subpopulations). The efficiency of colony-formation, the size of colonies, and the number of early osteogenic progenitors with alkaline phosphatase activity in colonies and induced osteogenesis were analyzed.

[Mesenchymal stem cells: sources, phenotype, and differentiation potential].

Mesenchymal stem cells present in the bone marrow and some other organs are primitive pluripotent precursors of osseous, cartilaginous, adipose, and other mesenchymal tissues. The recently revealed capacity of these cells for differentiation into nonmesenchymal derivatives is of considerable theoretical and practical interest. However, many aspects of the biology of these cells remain obscure despite active research.